#include<bits/stdc++.h>
using namespace std;
#define int long long
signed main() {
//	system("start https://www.lanqiao.cn/problems/8210/learning/");

	string s;
	cin >> s;
	if (s.end()[-1] == 'z')
		cout << s + "zz";
	else
		cout << s + "z";

	return 0;
}
